Processing refers to the individual or collective mechanical treatments
applied to single or multiple feed components during the manufacture of compound
aquatic feeds. These processes are carried out to modify the physical and
nutritional properties of the ingredients and of the finished feed to ensure
a consistent quality product. Key processes may include: batching, mixing,
particle size reduction, conditioning, agglomeration, post pellet conditioning,
fat coating, drying/cooling, crumbling and bagging.

Magnets should be located above all processing equipment and be checked
and cleaned as required by the production superintendent. Failure to capture
tramp iron may result in expensive repairs to equipment, injury to personnel,
contamination of product, delivery delays, or all of these problems at once,
including customer dissatisfaction.

Production runs of medicated feeds manufactured on processing equipment
should be grouped together as much as possible. When sequencing is not possible,
the processing system should be flushed with ground corn meal, or similar
ingredient. Flush material should be routed into the same medicated batch,
whenever possible.

All equipment operators should be familiar with basic equipment operation,
such as that contained in the particle size reduction operators manual,
pellet mill operators manual, extrusion operators manual or other
mill equipment manuals.

Before starting the equipment, the operator should check the flow of the
product to its destination to prevent cross-contamination. Particle size reducing
machinery (hammer mills, roller mills, etc.) should be routinely checked for
correct particle size.

When pelleting, product should be checked for pellet durability and pellet
water stability where appropriate (Tacon & Obaldo, 2001).

Proper conditioning with steam will enhance the process of starch gelatinisation,
which in addition to enhancing digestibility also improves pellet stability
in water (Bartone, 1999).

For extrusion of the formula, the product should be checked for shape,
bulk density, floating, slow sinking, or sinking, and also routinely checked
for correct particle size (McEllhiney, 1994).

Turnheads, distributors, diverter valves and spouting should be routinely
checked for operability, leaks and accuracy. The miller must know that the
ingredients are reaching the processing destination intended.